LED rotation: where is the cathode actually?

Recurring phenomenon: how do you rotate an LED correctly?

In 99% of cases, an LED sits in the tape with the cathode on the left side. The IPC recommendation is to mark the cathode. But what if the anode is marked and the LED sits in the tape with the anode on the left?

At DeltaProto B.V., we always make 1 or 2 samples first. During testing, it quickly becomes clear whether the orientation is correct. Did it go wrong? Then we fix it on the remaining proto-PCBA's.

Mistakes are educational: you discover that the anode was marked and take this information into the zero series. This way you prevent repetition and save time and costs.

What do you do? Do you fully investigate it first or do you learn from your mistakes?

PS the picture is of the LED in question and it really puts you on the wrong track!

PCBAProtoLabLearnings